Implantable electrical stimulation systems have proven therapeutic in a variety of diseases and disorders. For example, spinal cord stimulation systems have been used as a therapeutic modality for the treatment of chronic pain syndromes. Peripheral nerve stimulation has been used to treat chronic pain syndrome and incontinence, with a number of other applications under investigation. Functional electrical stimulation systems have been applied to restore some functionality to paralyzed extremities in spinal cord injury patients.
Stimulators have been developed to provide therapy for a variety of treatments. A stimulator can include a control module (with a pulse generator), one or more leads, and an array of stimulator electrodes on each lead. The stimulator electrodes are in contact with or near the nerves, muscles, or other tissue to be stimulated. The pulse generator in the control module generates electrical pulses that are delivered by the electrodes to body tissue.
Often leads are anchored at one or more places within the body to prevent or reduce the movement of the lead or stimulator electrodes after implantation. Such undesired movement of the leads may lead to: (1) damage to surrounding tissue; (2) movement of the stimulator electrodes out of their desired positions in such a way as to reduce effectiveness of treatment; or (3) interference or interruption in the connections between the stimulator electrodes and the control module.